Is there a way to distinguish nouns and verbs that applies to all languages?
This problem has been occupying my mind for some time now. I'm not quite sure how to approach this question, so I'll just list out some of my thoughts that make this question difficult:
- The usual grade school definition of a noun is a person, place, or thing, while a verb is defined as an action or state of being. This doesn't work so well when confronted with words like reenactment which is a noun that clearly refers to an action, or to locate which seems like it refers to a concept of place.
- Some words can clearly fall in both categories, like struggle, which is both noun and verb at once. (Though my belief is that the categories can exist independently, even if many words cross into both categories.)
- What's the difference between a language that has verbs like "to be a book", and languages that allow you to string nouns together making "X Y" the same meaning as "X is Y"?
The general feel I'm getting from all this is that nouns and verbs are distinguished by their roles in a sentence, not from the concepts they refer to, but I'm having a hard time formalizing this.
Follow-up: It seems like people are getting thrown off by all the thoughts I listed out above. Here's another way of restating the question:
If you have two classes of words in a language, how do you know which one is nouns and which one is verbs?